hellotbone

Anyone know what alternator comes in my 02 I think mine is going south! This morning I left the house and it went to negative red. So I drive it to work anyways pop the meter on it and its charging. So I shut the truck off then restart and the gauge starts working again.??? I don't know what to think anyways with my compressors and such I think I should go bigger so what do I have and what can I replace it with that is bigger! ;D

doug

Jamie, there are some simple steps to help you check things out. It's possible that with all your stereo equipment you could be taxing your alt, but you don't really know without some testing. If the starter still snaps good when you start the engine, then your batteries are happy and that can only happen when the charging system is good.<br><br>From your description I'd say you have a connection problem with your guage (or the gauge itself), not an alt problem per se. some time when the guage isn't working, perform the following tests:<br><br>hang a voltmeter on your battery terminals. It should read approximately 12v engine off. a bit more than that if you have a battery with surface charge on it (recently charged or overcharged -- you can take the surface charge off by bumping the starter or turning on the lights for a minute).<br><br>Anyway, assuming you have 12v at the battery, start the truck and measure again. a working alternator and a fully charged battery should result in about 14.5v at the battery terminals. you should recognize that number from the car stereo world, but it comes from the normal output of a stock working alternator against a fully charged battery. If you've got 14.5v then your alternator is probably working. <br><br>next test is to discharge your battery a bit (never deep discharge a starting battery so be careful here) by leaving the headlights on for 10 minutes, engine off. then repeat the same two measurements (engine on and engine off). You should still measure close to 11.5-12v engine off, and perhaps 13-13.5v engine on. watch the voltmeter climb -- your alternator output should climb from the 13v region to the 14.5v region as the battery charges. If so, then your alt is working just dandy.<br><br>But if your alt is breaking, I'd seriously get an after market racing alt from the likes of powermaster. The stock alt is pretty wimpy, especially at idle, but the PowerMaster guys have tremendous output at idle speeds. I had an old 1982 Chev diesel that I put a PowerMaster in. the thing was so powerful I had to watch the belt tension really close or it would slip.<br><br>Batteries and alternators are one of those things where there are onlyl advantages and no disadvantage. <br><br>oh, and one more thing. dispel the myth from car audio that stiffening caps save alternators. they don't!

hellotbone

Caps are the biggest waste of money I have ever seen you should see how many kids argue with me that they NEED a cap anyways I found the problem to be a loose connection on the gauge maybe from all that earth shattering bass ;D anywas my alternator is very happy now putting out 14.5 volts idle and 12 volts truck off!

doug

heh heh heh. glad you found your gauge problem, and good for you on the expensive caps. I went through a bunch of calculations once and discovered that the equivalent series resistance and the equivalent series inductance of the caps pretty much negate supposed benefit. And in the vast majority of cases the money is better spent on wires and a PowerMaster alternator.<br><br>Good to see that you don't subscribe to the snake oil!

1ST CUMNZ

136 AMP FOR DIESELS

hellotbone

Thanks 1st Cummins I wanna get upwards around 180 amps.

doug

http://www.powermastermotorsports.co..._high_amp.html<br><br>I don't remember if our alternators' mounting brackets are at 12 o'clock and 6 o'clock but if they are then this one should work. Otherwise PM doesn't have one for us. <br><br>Also check out Ohio Generator. they don't sell direct, but maybe you could become a dealer ;D<br><br>Those are the two biggest names in high output alternators. Beware of shops that re-wind your current core and expect really high output -- the heat dissipation may become problematic, even if they upgrade your brushes. However this method is good to around 20-25%% increase in output<br><br>If you're inclined to disassemble and re-assemble your alt, you can buy high output field windings (or a kit with windings and new brushes) and get the 25% or so increase, which is all you need to get to 170 from 136. I'm saying that if 170 is your goal, then consider upgrading your current core or having yours re-wound. it will require some research but its definately doable. BTW &quot;rewinding&quot; an alternator is nothing more than dropping in a new field winding with more turns in it. An hours worth of work.<br><br>If you want a clean slam dunk you can get into the 200A category with ohio generator I think.<br><br>I've had personal experience with PowerMaster and I was pleased. The bonus of buying a new alt (PowerMaster or otherwise) is that you have a good working stock alt to use as a backup. <br><br>If I were in your shoes I'd look at the PowerMaster first (checkout the mounting situation). probably $200 or so. Then go to an after market winding shop (or DIY) to upgrade yours if all you want is a 20-25% increase in output (170A). If you want more, then go to ohio generator and get into the 200A neighborhood and around $450 plus.